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Adding data from .txt document to array

Below is what the text document looks like. The first line is the number of elements that I want the array to contain. The second is the ID for the product, separated by # and the third line is the total price of the products once again separated by #
10
PA/1234#PV/5732#Au/9271#DT/9489#HY/7195#ZR/7413#bT/4674#LR/4992#Xk/8536#kD/9767#
153#25#172#95#235#159#725#629#112#559#
I want to use the following method to pass inputFile to the readProductDataFile method:
public static Product[] readProductDataFile(File inputFile){
// Code here
}
I want to create an array of size 10, or maybe an arrayList. Preferably to be a concatenation of Customer ID and the price, such as Array[1] = PA/1234_153

There you go the full class, does exactly what you want:
import java.io.BufferedReader;
import java.io.FileReader;
import java.util.Arrays;
import java.io.FileNotFoundException;
import java.io.IOException;
class myRead{
public static void main(String[] args) throws FileNotFoundException, IOException {
BufferedReader inputFile = new BufferedReader(new FileReader("test.txt"));
String numberOfElements = inputFile.readLine();
//this is the first line which contains the number "10"
//System.out.println(numberOfElements);
String secondLine = inputFile.readLine();
//this is the second line which contains your data, split it using "#" as a delimiter
String[] strArray = secondLine.split("#");
//System.out.println(Arrays.toString(strArray));
//System.out.println(strArray[0]);
String thirdLine = inputFile.readLine();
//this is the third line which contains your data, split it using "#" as a delimiter
String[] dataArray = thirdLine.split("#");
//combine arrays
String[] combinedArray = new String[strArray.length];
for (int i=0;i<strArray.length;i++) {
combinedArray[i]=strArray[i]+"_"+dataArray[i];
System.out.println(combinedArray[i]);
}
}
}
OUTPUT:
PA/1234_153
PV/5732_25
Au/9271_172
DT/9489_95
HY/7195_235
ZR/7413_159
bT/4674_725
LR/4992_629
Xk/8536_112
kD/9767_559
The trick in what I am doing is using a BufferedReader to read the file, readLine to read each of the three lines, split("#"); to split each token using the # as the delimiter and create the arrays, and combinedArray[i]=strArray[i]+"_"+dataArray[i]; to put the elements in a combined array as you want...!
public static Product[] readProductDataFile(File inputFile){
BufferedReader inputFile = new BufferedReader(new FileReader(inputFile));
// the rest of my previous code goes here
EDIT: Everything together with calling a separate method from inside the main, with the file as an input argument!
import java.io.BufferedReader;
import java.io.FileReader;
import java.util.Arrays;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.File;
class myRead{
public static void main(String[] args) throws FileNotFoundException, IOException {
File myFile = new File("test.txt");
readProductDataFile(myFile);
}
public static String[] readProductDataFile(File inputFile) throws FileNotFoundException, IOException{
BufferedReader myReader = new BufferedReader(new FileReader("test.txt"));
String numberOfElements = myReader.readLine();
//this is the first line which contains the number "10"
//System.out.println(numberOfElements);
String secondLine = myReader.readLine();
//this is the second line which contains your data, split it using "#" as a delimiter
String[] strArray = secondLine.split("#");
//System.out.println(Arrays.toString(strArray));
//System.out.println(strArray[0]);
String thirdLine = myReader.readLine();
//this is the third line which contains your data, split it using "#" as a delimiter
String[] dataArray = thirdLine.split("#");
//combine arrays
String[] combinedArray = new String[strArray.length];
for (int i=0;i<strArray.length;i++) {
combinedArray[i]=strArray[i]+"_"+dataArray[i];
System.out.println(combinedArray[i]);
}
return combinedArray;
}
}
OUTPUT
PA/1234_153
PV/5732_25
Au/9271_172
DT/9489_95
HY/7195_235
ZR/7413_159
bT/4674_725
LR/4992_629
Xk/8536_112
kD/9767_559

You don't even need the first line. Just read the second line directly into a single string and then split it by using String,split() method.
Read more for split method here.

You could use something like this (Be aware that i can't test it at the moment)
BufferedReader in = null;
try {
in = new BufferedReader(new FileReader("fileeditor.txt"));
String read = null;
String firstLine=in.readLine();
//reads the first line
while ((read = in.readLine()) != null) {
// reads all the other lines
read = in.readLine();
String[] splited = read.split("#");
//split the readed row with the "#" character
for (String part : splited) {
System.out.println(part);
}
}
} catch (IOException e) {
System.out.println("There was a problem: " + e);
e.printStackTrace();
} finally {
try {
//close file
in.close();
} catch (Exception e) {
}
}

This is how you can do it using Java (don't forget to import):
public static Product[] readProductDataFile(File inputFile){
Scanner s = new Scanner(inputFile);
String data = "";
while(s.hasNext())
data += s.nextLine();
String[] dataArray = data.split("#");
}

You can try this way ..
Reading line by line and storing each row in a array.
Use while storing so it will split and save .
String[] strArray = secondLine.split("#");
Now use the for loop and concat the values as u wish and save ina third array .
For(int i=0 ;i< file.readline;i++)
{
string s = a[customerid];
s.concat(a[productid]);
a[k] =s;
}

JAVA String Reversing order of string in file io

I have to write code that will reverse the order of the string and write it in a new file. For example :
Hi my name is Bob.
I am ten years old.
The reversed will be :
I am ten years old.
Hi my name is Bob.
This is what I have so far. Not sure what to write for the outWriter print statement. Any help will be appreciated. Thanks!
import java.io.*;
import java.util.ArrayList;
import java.util.Scanner;
public class FileRewinder {
public static void main(String[] args) {
File inputFile = new File("ascii.txt");
ArrayList<String> list1 = new ArrayList<String>();
Scanner inputScanner;
try {
inputScanner = new Scanner(inputFile);
} catch (FileNotFoundException f) {
System.out.println("File not found :" + f);
return;
}
while (inputScanner.hasNextLine()) {
String curLine = inputScanner .nextLine();
System.out.println(curLine );
}
inputScanner.close();
File outputFile = new File("hi.txt");
PrintWriter outWriter = null;
try {
outWriter = new PrintWriter(outputFile);
} catch (FileNotFoundException e) {
System.out.println("File not found :" + e);
return;
}
outWriter.println(???);
outWriter.close();
}
}

My suggestion is read entire file first and store sentences(you can split by .) in a LinkedList<String>(this will keep insertion order)
Then use Iterator and get sentences in reverse order. and write them into a file. make sure to put . just after each sentence.

After System.out.println(curLine ); add list1.add(curline); that will place your lines of text into your list.
At the end create a loop over list1 backwards:
for(int i = list1.size() - 1 , i > 0, --i) {
outWriter.println(list1[i]);
}

If the file contains an amount of lines which can be loaded into the memory. You can read all lines into a list, reverse the order of the list and write the list back to the disk.
public class Reverse {
static final Charset FILE_ENCODING = StandardCharsets.UTF_8;
public static void main(String[] args) throws IOException {
List<String> inLines = Files.readAllLines(Paths.get("ascii.txt"), FILE_ENCODING);
Collections.reverse(inLines);
Files.write(Paths.get("hi.txt"), inLines, FILE_ENCODING);
}
}

Read a text file to an array Java

I know there are many questions about reading text files here but I have gone through all of them and I think I'm having some difficulty with syntax or SOMETHING because nothing that I've been trying has been working at all.
What I'm attempting to do is this:
1) read a text file inputed by user
2) copy each individual line into an array, so each line is its own element in the array
I feel like I am very close but for some reason I can't figure out exactly how to get it to work!
Here is the relevant code I have right now:
I keep getting out of bounds exceptions in three locations which I've marked off.
Been working on this for quite a while not sure what to do next! Any ideas?
import java.io.IOException;
import java.util.Scanner;
public class FindWords {
public static void main (String args[]) throws IOException{
FindWords d = new Dictionary();
((Dictionary) d).dictionary(); //********* out of bounds here
}
/**
* Validates and returns the dictionary inputed by the user.
*
* #param
* #return the location of the dictionary
*/
public static String getDict(){
///////////////////ASK FOR DICTIONARY////////////////////
System.out.println("Please input your dictionary file");
//initiate input scanner
Scanner in = new Scanner(System.in);
// input by user
String dictionary = in.nextLine();
System.out.println("Sys.print: " + dictionary);
//make sure there is a dictionary file
if (dictionary.length() == 0){
throw new IllegalArgumentException("You must enter a dictionary");
}
else return dictionary;
}
}
which calls on the class Dictionary:
import java.io.*;
public class Dictionary extends FindWords{
public void dictionary () throws IOException{
String dict = getDict();
String[] a = readFile(dict); //********** out of bounds here
int i = 0;
while(a[i] != null){
System.out.println(a[i]);
i++;
}
}
public static String[] readFile(String input) throws IOException{
//read file
BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(input)));
System.out.println ();
int count = 0;
String[] array = new String[count];
try{
while (br.readLine() != null){
array[count] = br.readLine(); //********out of bounds here
count++;
}
br.close();
}
catch (IOException e){
}
return array;
}
}
Thank you for looking!
Edit: Just fyi: I have my .txt file in the parent project folder.

Have you tried this?:
List<String> lines = Files.readAllLines(Paths.get("/path/to/my/file.txt"));
and then transform your list to an array if you want:
String[] myLines = lines.toArray(new String[lines.size()]);

You start with an array size of zero...
int count = 0;
String[] array = new String[count];

Several issues here :
In Java, you can't expand arrays, i.e you have to know their length in advance when you instantiate them. Hence the ArrayOutOfBoundException. To make this easy, I suggest that you use an ArrayList instead.
In your while loop, you're making 2 calls to br.readLine(), so basically you're skipping one line out of 2.

You are initializing a zero-length array, hence the exception on the first iteration:
int count = 0;
String[] array = new String[count];
Since you probably don't know the expected size, work with a List instead:
List<String> list = new ArrayList<>();
String thisLine = null;
try{
while ((thisLine = br.readLine()) != null) {
list.add(thisLine);
}
}
You can get the total size afterwards by:
list.size();
Or even better, go with morganos solution and use Files.readAllLines().

Identifying each word in a file

Importing a large list of words and I need to create code that will recognize each word in the file. I am using a delimiter to recognize the separation from each word but I am receiving a suppressed error stating that the value of linenumber and delimiter are not used. What do I need to do to get the program to read this file and to separate each word within that file?
public class ASCIIPrime {
public final static String LOC = "C:\\english1.txt";
#SuppressWarnings("null")
public static void main(String[] args) throws IOException {
//import list of words
#SuppressWarnings("resource")
BufferedReader File = new BufferedReader(new FileReader(LOC));
//Create a temporary ArrayList to store data
ArrayList<String> temp = new ArrayList<String>();
//Find number of lines in txt file
String line;
while ((line = File.readLine()) != null)
{
temp.add(line);
}
//Identify each word in file
int lineNumber = 0;
lineNumber++;
String delimiter = "\t";
//assess each character in the word to determine the ascii value
int total = 0;
for (int i=0; i < ((String) line).length(); i++)
{
char c = ((String) line).charAt(i);
total += c;
}
System.out.println ("The total value of " + line + " is " + total);
}
}

This smells like homework, but alright.
Importing a large list of words and I need to create code that will recognize each word in the file. What do I need to do to get the program to read this file and to separate each word within that file?
You need to...
Read the file
Separate the words from what you've read in
... I don't know what you want to do with them after that. I'll just dump them into a big list.
The contents of my main method would be...
BufferedReader File = new BufferedReader(new FileReader(LOC));//LOC is defined as class variable
//Create an ArrayList to store the words
List<String> words = new ArrayList<String>();
String line;
String delimiter = "\t";
while ((line = File.readLine()) != null)//read the file
{
String[] wordsInLine = line.split(delimiter);//separate the words
//delimiter could be a regex here, gotta watch out for that
for(int i=0, isize = wordsInLine.length(); i < isize; i++){
words.add(wordsInLine[i]);//put them in a list
}
}

You can use the split method of the String class
String[] split(String regex)
This will return an array of strings that you can handle directly of transform in to any other collection you might need.
I suggest also to remove the suppresswarning unless you are sure what you are doing. In most cases is better to remove the cause of the warning than supress the warning.

I used this great tutorial from thenewboston when I started off reading files: https://www.youtube.com/watch?v=3RNYUKxAgmw
This video seems perfect for you. It covers how to save file words of data. And just add the string data to the ArrayList. Here's what your code should look like:
import java.io.*;
import java.util.*;
public class ReadFile {
static Scanner x;
static ArrayList<String> temp = new ArrayList<String>();
public static void main(String args[]){
openFile();
readFile();
closeFile();
}
public static void openFile(){
try(
x = new Scanner(new File("yourtextfile.txt");
}catch(Exception e){
System.out.println(e);
}
}
public static void readFile(){
while(x.hasNext()){
temp.add(x.next());
}
}
public void closeFile(){
x.close();
}
}
One thing that is nice with using the java util scanner is that is automatically skips the spaces between words making it easy to use and identify words.

2d array doesn't print (or perhaps fill) correctly

In my main class, I loop through 120 files. For each file I create a 2d array of the data contained within.
My 2d Array is "fullData" of type List<List<String>>. ParserIPAM is an inherited class and i declare fullData in its super class.
This is my code within main:
for(String filename : filefetcher.getFiles()){
System.out.println("file to parse: "+ filename);
ipam = new ParserIPAM(filename);
i=0;
boolean flag = true;
System.out.println("------------------------------------------");
for(List<String> row : ipam.getSqlData()){
//queries.insertVars(row);
//System.out.println(row);
}
//System.out.println(i);
ipam.clearSqlData();
}
And here is my code where I fill the 2d Array:
public ParserIPAM(String filename){
super(filename);
try {
Parse(filename);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
SpecialOperations(fullData);
//System.out.println("+++++++++++++++++++++++++++++++++++"+ls2d.size());
}
#Override
void Parse(String filename) throws FileNotFoundException{
fullData.clear();
FileReader input = new FileReader(filename);
ArrayList<String> Raw = new ArrayList<String>();
BufferedReader bufRead = new BufferedReader(input);
Scanner bufferinput = new Scanner(bufRead);
String nextline = bufferinput.nextLine();
int i = 0;
while(bufferinput.hasNext()){
Raw.clear();
nextline = bufferinput.nextLine();
for(String cell: nextline.split(",(?=([^\"]*\"[^\"]*\")*[^\"]*$)")){
Raw.add(cell);
//System.out.print(i+" "+cell); ////// THIS PRINTS CORRECT DATA
}
i++;
//System.out.println(i + " " + Raw); ////THIS PRINTS CORRECT DATA
fullData.add(Raw);
}
for(List<String> sub: fullData){
//System.out.println(sub); ///THIS DOES NOT PRINT CORRECTLY
}
}
Edit: ParserIPAM is an inherited class. Here is the complete code for the super class:
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
public abstract class Parser {
protected static String filename;
//private List<List<String>> dataArray = new ArrayList<ArrayList<String>()>();
protected List<List<String>> fullData = new ArrayList<List<String>>();
public Parser(String filename){
//this.filename = filename;
}
//Parse will only parse file and put raw data into a 2d ArrayList.
abstract void Parse(String filename) throws FileNotFoundException;
//SpecialOperations will add additional data to raw data for table insertions.
abstract void SpecialOperations(List<List<String>> data);
}
When I print everything out in the last System.out it prints the correct number of elements (256) but it always prints out the last line of the file 256 times in a row. I'm not exactly sure if I'm filling the array incorrectly or if I'm printing it incorrectly. Either way its wrong and I can't seem to figure it out.
I know there is probably a better way to do this than with an ArrayList, but that's not affecting the issue I'm having.

You only create one ArrayList instance (and clear it in your loop), so you only have one reference added (just many times). For Java 7 and above, the easiest solution I can think of is to use new ArrayList<>() diamond operator instead -
// Raw.clear();
Raw = new ArrayList<>();
for Java 6 and 5,
// Raw.clear();
Raw = new ArrayList<String>();
Similarly, you could also use this instead -
// fullData.add(Raw);
fullData.add(new ArrayList<>(Raw)); // <-- copies Raw

Try putting the instantiation of Raw inside the While loop
while(bufferinput.hasNext()){
ArrayList<String> Raw = new ArrayList<String>();
Raw.clear();
nextline = bufferinput.nextLine();
for(String cell: nextline.split(",(?=([^\"]*\"[^\"]*\")*[^\"]*$)")){
Raw.add(cell);
//System.out.print(i+" "+cell); ////// THIS PRINTS CORRECT DATA
}
i++;
//System.out.println(i + " " + Raw); ////THIS PRINTS CORRECT DATA
fullData.add(Raw);
}